ATI RN
Cardiovascular System Test Questions Questions
Question 1 of 5
Which of the following has single layer of endothelial structure?
Correct Answer: C
Rationale: Capillaries (C) consist of a single endothelial layer for exchange. Arteries (A) and veins (B) have multiple layers (tunicae), and lymphatics (D) have thin walls but valves.
Question 2 of 5
Absolute period when whole heart is in diastole is:
Correct Answer: D
Rationale: Joint diastole (all chambers relaxed) is ~0.4 s (D) at 75 bpm (0.8 s cycle - 0.4 s systole). A is too long, B and C too short.
Question 3 of 5
Which layer of the heart wall consists of cardiac muscle tissue?
Correct Answer: C
Rationale: The myocardium (C) is the thick muscular layer of the heart responsible for contraction. Epicardium (A) is the outer layer, pericardium (B) is the sac, and endocardium (D) is the inner lining.
Question 4 of 5
The volume of blood ejected from the left ventricle into the aorta each minute is called the
Correct Answer: A
Rationale: Cardiac output (A) is the volume ejected per minute (stroke volume × heart rate, ~5 L/min). Stroke volume (C) is per beat, heart rate (D) is beats per minute, and cardiac input (B) is not a term.
Question 5 of 5
Which of the following most accurately describes what is measured by an electrocardiogram?
Correct Answer: D
Rationale: An ECG measures electrical activity to detect abnormalities (D), indirectly reflecting rate and rhythm.